Grate zucchini, then place between a few sheets of paper toweling to remove excess moisture. Set aside.
In a medium size bowl, add millet flour, blanched almond flour, light buckwheat flour, psyllium husk powder, baking powder, baking soda, salt and pepper. Whisk to combine, then set aside.
In a small bowl, add almond milk and apple cider vinegar. Stir to combine, then set aside.
In a large bowl, add the eggs and whisk until pale and frothy. Next add the almond milk and apple cider vinegar mixture and olive oil. Whisk to combine. Then add the flour mixture and stir to combine. Finally fold in grated zucchini and chopped toasted nuts.
Add basil leaves, toasted nuts, garlic, salt and fresh lemon juice to the bowl of a food processor. Process until mixture forms a paste, then gradually add oil, processing until mixture is smooth.
Pesto can be stored in an airtight container in the refrigerator for up to one week. Pesto can also be frozen. Freeze in an ice cube tray, then store frozen cubes in a plastic freezer bag.